1. Field of the Invention
The present invention relates to a sheet conveying device for conveying a sheet so as to discharge the sheet onto a tray, and also to an image recording apparatus including the sheet conveying device.
2. Discussion of Related Art
In an image reading apparatus equipped with an automatic document feeder (ADF), a document disposed on a document tray is conveyed along a path, an image carried on the document is read in the process of conveyance of the document. After the image has been read, the document is discharged onto an exit tray. As an example of such an image reading apparatus, JP-H06-247608A discloses an apparatus in which a haul member and ribs are provided on an upper surface of an exit tray. Each of the ribs extends vertically from the upper surface of the exit tray and is elongated in a discharging direction in which a document is to be discharged. The haul member is provided by a plate-like member that is elongated in the discharging direction. An end fence is provided in an upstream end portion of the haul member in the discharging direction, while a tab is provided in a downstream end portion of the haul member in the discharging direction. After the document has been discharged onto the exit tray, a user slides the haul member in the discharging direction by operating the tab. The thus slid haul member is brought into contact with a trailing end of the document, and the document is moved along the ribs in the downstream direction.
JP-H10-316299A discloses a post-processing apparatus for stapling recording sheets after an image recording operation performed onto the recording sheets, and for discharging the stapled recording sheets onto an exit tray. In this post-processing apparatus, a pair of protruding members are provided on the exit tray. Specifically described, the protruding members are disposed on a contact portion of an upper surface of the exit tray, with which a sheaf of the discharged recording sheets hanging down is brought into contact at its leading end. The protruding members are located on respective opposite sides of a centerline of the exit tray (that extends in the discharging direction). Each of the protruding members has a gently inclined upper surface so as to have a height that is gradually reduced as viewed in a direction toward the centerline. Since the sheaf of the recording sheets is conveyed along the inclined upper surfaces of the respective protruding members, the sheaf is slightly warped at its leading end portion and accordingly given rigidity that restrains the sheaf from being rolled.
A conventional image recording apparatus such as an inkjet printer is provided with a sheet supplying cassette, which is constituted by a double-deck tray assembly including upper and lower portions that are provided by a sheet exit tray and a sheet supply tray, respectively. Each of the sheet tray and the sheet exit tray is expandable and contractible in the discharging direction so as to be capable of holding a recording sheet of any one of various sizes, so as to hold the sheet of a selected one of the various sizes. The sheet exit tray is provided with an extension tray for supporting a leading end portion of a recording sheet discharged onto the sheet exit tray. The extension tray is provided in a downstream end portion of the sheet exit tray in the discharging direction, and protrudes upwardly from an upper surface of the sheet exit tray. The recording sheet discharged onto the sheet exit tray is supported at its leading end by the extension tray, so as to be prevented from dropping from the sheet exit tray.
FIG. 15 is a perspective view showing a conventional sheet supplying cassette 149 with a state in which a recording sheet 137 discharged onto a sheet exit tray 144 has been brought into contact at its leading end with a stopper 148 so as to be stopped before discharge of the sheet 137 is completed. This state, which could be caused where the stopper 148 is movable in the discharging direction or the discharged recording sheet 137 has such a large length that its leading end reaches a downstream side of the stopper 148 in the discharging direction, could cause a risk of problematic jamming of the recording sheet 137. Such a problem could occur not only where the sheet supplying cassette 149 is used for supplying a recording sheet in an image recording apparatus but also where it is used for supplying a document in a scanner apparatus.